Ueber die Umkehrung der Systeme von Functionen reeller Variabeln

Ohne Zusammenfassung     

Harmonic generation with non collinear laser beams. Application to pulse stacking

Harmonic generation in KDP crystals is of great interest in application to high power Nd laser chains. A non collinear beams technique has been investigated numerically and experimentally. It has been pointed out that an optimum separation angle can be found where tolerance on divergence of one beam is increased. The process provides angular separation of the fundamental and harmonic beams and allows a pulse stacking compression technique, which is described, and which could improve the performances of a laser chain.     

The He(Iα) Photoelectron Spectra of Substituted 1,2-Dithietes

The He(Iα) photoelectron (PE.) spectra of a series of substituted 1,2-dithietes have been recorded and assigned with respect to the orbital sequence derived from an STO-3G model calculation and by correlation with the PE. spectra of related compounds. The results provide additional support for the presence of a closed, four-membered ring moiety in all the 1,2-dithietes investigated. In all cases the two highest occupied molecular orbitals are b₂(π)= HOMO, a₂(π), with exception of 3,4-bis(trifluoromethyl)-1,2-dithiete where the sequence b₂(π), a₂(π) or a₂(π), b₂(π) is uncertain.     

Mehrfachbindungen zwischen hauptgruppenelementen und übergangsmetallen: IV. Chrom-schwefel- und chrom-selen-bindungen: Knüpfung,umwandlungsreaktionen und alkylidenaddition

New dinuclear chromium—sulfur complexes containing one or two sulfur atoms are formed upon reaction of the ionic complex K[(η⁵-C₅Me₅)Cr(CO)₃] (Me = CH₃; 1) with trithiazyl trichloride at temperatures below ambient. The μ(η¹ :η²)-disulfur complex 2a of composition (η⁵-C₅Me₅)₂Cr₂(CO)₅S₂ undergoes concomitant CO-elimination and desulfurization on heating or in the presence of triphenylphosphine; the CrSCr-complex (η⁵-C₅Me₅)₂Cr₂(CO)₄S (2c) is formed in these cases. When diazomethane is treated with 2a, a novel μ,η²-thio- formaldehyde complex (2d) results, again following CO- and S-extrusion. While the triple-bonded CrSCr-skeleton present in 2c does not allow alkylidene additions, such reactions, which proceed cleanly, are observed with the corresponding μ⁵-seleno derivative (η⁵-C₅H₅)₂Cr₂(CO)₄Se (4) synthesized from Na[(η⁵-C₅H₅)Cr(CO)₃] and sodium selenite in the presence of hydrochloric acid.     

Electron exchange chemiluminescence from a sterically stabilized cyclobutadiene-1,2-dioxetane

The rather stable 1,2-dioxetanes ($\text{2}$) and ($\text{3}$), derived from the sterically stabilized cyclobutadiene ($\text{1}$), exhibit distinct enhanced chemiluminescence behavior, namely energy transfer chemiluminescence (ETC) for ($\text{2}$) and electron exchange chemiluminescence (EEC) for ($\text{3}$).     

Massenspektrometrische Bestimmung der thermodynamischen Aktivitäten von flüssigen Gold-Kobalt-Legierungen

The thermodynamic activities and the heats of mixing of liquid Au–Co alloys have been determined using aKnudsen cell in combination with a mass spectrometer. At 1770 K the maximum value of the excessGibbs free energy, G ^E, is 790 cal/g-atom (63 at% Co), the maximum value of the heat of mixing, H, is 1930 cal/g-atom (42 at% Co).

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Mit 9 Abbildungen

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Herrn Prof. Dr.Richard Kieffer zum 70. Geburtstag gewidmet.